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1.
We report a 20 month old female patient with diploid-triploid mixoploidy (46,XX/69,XXX) syndrome with hypothyroidism and precocious puberty. The triploid cell line was only expressed in the fibroblast culture and comprised the majority (95%) of the cells. Chromosome analysis of the fetal blood sample and peripheral blood sample were normal. The patient shows typical features of full triploidy (growth and severe mental retardation, cranial and facial dysmorphism, complete syndactyly of fingers 3/4, partial syndactyly of toes 2/3) and facial but no body asymmetry. At the age of 5 months central hypothyroidism and precocious puberty were diagnosed. Thin pigmented streaks were visible on the wrists and legs of the patient at the age of 16 months. This is the first patient reported so far with 46,XX/69,XXX mixoploidy suffering from hypothyroidism and precocious puberty.  相似文献   
2.
A new oxidative pathway for the degradation of caffeine(1,3,7-Trimethylxanthine, I) by a mixed culture consisting of strains belonging to the genera Klebsiella and Rhodococcus is presented. The mixed culture does not initiate degradation by N-demethylation either complete or partial, but instead carries out oxidation at the C-8 position resulting in the formation of 1,3,7-trimethyluric acid (TMU, II) which further gets degraded to 3,6,8-trimethylallantoin (TMA, III). Both TMU and TMA are hitherto not shown to be formed in the microbial system. Further degradation of TMA (III) by caffeine grown cells yields dimethylurea (VII) as one of the metabolites. Oxygen uptake studies indicated that caffeine(I) grown cells oxidized TMU(II), TMA (III), glyoxalic acid (VI), dimethylurea(VII), and monomethylurea(V), but not monomethyl and dimethyluric acids. The mixed culture does not accept theophylline(1,3-dimethylxanthine), theobromine(3,7-dimethylxanthine), and paraxanthine(1,7-dimethylxanthine) as the carbon source.  相似文献   
3.
Male and female A/J mice were examined for their ability to elicit T lymphocyte and antibody (Ab) responses to the male-specific Ag, mouse testicular cytochrome c (Mt cyt). T lymphocytes from both male and female mice primed in vivo responded to the Ag in in vitro proliferation assays, and the dose-response curves were statistically indistinguishable. In addition, similar levels of Ab to Mt cyt were observed in immunized male and female mice. The B cells producing the Ab had switched isotypes to IgG1 and IgG2a, indicating that the self-reactive T helper (Th) cells in male mice were functional. Thus, male mice do not appear to be immunologically tolerant to Mt cyt, at least at the Th and B lymphocyte levels. No evidence for disease was found in male mice primed with Mt cyt. Major histocompatibility complex (MHC) class II-positive antigen-presenting cells are present in the testes and these were shown in vitro to process and present Mt cyt to a T cell hybridoma specific for the synthetic peptide Mt cyt 93-104. However, the hybridoma was not activated in the absence of exogenous Mt cyt 93-104 or Mt cyt, indicating that endogenous Mt cyt is not normally processed in sufficient quantity to effectively load MHC class II molecules with this particular Mt cyt-derived peptide. Notwithstanding any immunologic privilege of the testes, the lack of tolerance to Mt cyt and its failure to elicit an autoimmune disease could extend from the low levels of processed Mt cyt Ag available for T cell recognition. The T cell response elicited by Mt cyt contrasts the lack of response to mouse somatic cytochrome c which differs from Mt cyt at 13 amino acid residues and is expressed in most tissues and at higher levels.  相似文献   
4.
Petroleum asphaltenes have been precipitated in solvent mixtures of n-heptane and toluene at various temperatures, likewise n-heptane asphaltenes have been dissolved in under similar conditions. This give added evidence to apparent hysteresis phenomenon between the two processes. The Asphaltenes have been characterized showing that although data is scattered convergence to certain structural parameters as incipient flocculation is approached. The asphaltenes are seen to consist of an associating and a non-associating part. The solubility of asphaltenes has been correlated/modelled using the Flory-Huggins equation using two different terms for the Flory parameter. A process for evaluation of best choice of solubility parameter and molar volume for the asphaltenes is proposed. Dissolution processes are seen to be best fitted by the equations. Based on these findings the asphaltenes are proposed to be formed by a colloidal and a true solution part.  相似文献   
5.
Growth hormone (GH) has recently been shown to affect polymorphonuclear neutrophil granulocyte (PMN) function and to be secreted by mononuclear cells, indicating that the hormone may be active in an immunophysiologic network, acting as an endo- or paracrine priming agent. The purpose of the present study was to evaluate the chemotactic responsiveness of canine peripheral PMN in a dog with acromegaly, caused by spontaneous, progesterone-induced hypersecretion of GH and, secondary to this, a seven-fold increase in insulin-like growth factor I (IGF-I). The chemotactic responsiveness towards zymosan-activated serum (ZAS) and leukotriene B4 (LTB4) was evaluated at a time when the dog suffered from acromegaly and again 57 days after corrective surgery (ovariohysterectomy). The experiments showed that PMN from the patient exhibited enhanced chemotactic migration that appeared to be associated with the hypersomatotropic condition as judged from the reversibility of the phenomenon. The glucose intolerance and elevated serum alkaline phosphatase that were observed in the acromegalic dog were also shown to be reversible following surgery.  相似文献   
6.
Cells in the dorsal division of the medial superior temporal area (MSTd) have large receptive fields and respond to expansion/contraction, rotation, and translation motions. These same motions are generated as we move through the environment, leading investigators to suggest that area MSTd analyzes the optical flow. One influential idea suggests that navigation is achieved by decomposing the optical flow into the separate and discrete channels mentioned above, that is, expansion/contraction, rotation, and translation. We directly tested whether MSTd neurons perform such a decomposition by examining whether there are cells that are preferentially tuned to intermediate spiral motions, which combine both expansion/contraction and rotation components. The finding that many cells in MSTd are preferentially selective for spiral motions indicates that this simple three-channel decomposition hypothesis for MSTd does not appear to be correct. Instead, there is a continuum of patterns to which MSTd cells are selective. In addition, we find that MSTd cells maintain their selectivity when stimuli are moved to different locations in their large receptive fields. This position invariance indicates that MSTd cells selective for expansion cannot give precise information about the retinal location of the focus of expansion. Thus, individual MSTd neurons cannot code, in a precise fashion, the direction of heading by using the location of the focus of expansion. The only way this navigational information could be accurately derived from MSTd is through the use of a coarse, population encoding. Positional invariance and selectivity for a wide array of stimuli suggest that MSTd neurons encode patterns of motion per se, regardless of whether these motions are generated by moving objects or by motion induced by observer locomotion.  相似文献   
7.
8.
Determined the specific type of sexual functioning deficits and the relationship between global sexual satisfaction and adjustment in 2 related life areas (marital relationship and body image) for 2 groups of cancer patients at high risk for sexual difficulties. The 2 groups included 16 27–67 yr old females with Stage 2 breast cancer and 16 31–65 yr old females with gynecologic cancer. These Ss were compared to 16 healthy female outpatients (controls). Measures included the Sexual Activities scale from the Derogatis Sexual Functioning Inventory, a modified version of the Dyadic Assessment Scale (marital adjustment), a global sexual evaluation, and a body-image scale. Analyses revealed that the aspects of sexual functioning for breast-cancer and gynecologic-cancer Ss that differed from those of controls were the frequency of sexual behaviors and the level of sexual arousal. Whereas Ss' evaluations of their current sexual life had no relationship to their marital-adjustment ratings, analyses suggested that body-image disruption may be a prevalent problem for gynecologic cancer patients. Data suggest that cancer diagnosis and treatment are instrumental in producing reductions in sexual activity and arousability. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
In the bacterium Escherichia coli, H-NS-(H1, H1a) is a heat-stable protein with a molecular mass of 15.5 kDa involved in nucleoid organisation and gene regulation linked to certain signal transduction pathways. We have shown that, following addition of preparations of everted inner membrane vesicles, heat-stable cleavage products of approximately 10 kDa of H-NS are formed in vitro from newly synthesised, radio-labelled H-NS and from purified H-NS. The 15.5 kDa protein and its cleavage products were also recovered from a minicell system. These results raised the possibility that cleavage of H-NS is physiologically significant. However, the cleavage of H-NS observed appears to occur during cell breakage and to depend on the method of protein extraction and the presence of the outer membrane protease, OmpT. Nevertheless, the results indicate that H-NS may contain at least two separate domains with cleavage occurring between these domains at a preferred OmpT site. Failure to take account of H-NS cleavage in sample preparation and analysis can lead to serious underestimation of H-NS levels.  相似文献   
10.
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